Adobe Digital Editions takeover of pdf files

Recently I installed the more recent version of Adobe Digital Editions (the new one is 4.5. I had 3.0 -- in fact, I still have also 3.0, as I am not sure whether I can discard 3.0, since 4.5 took over files from 3.0). But then I saw that many of the pdf files on my computer (which were not Adobe Digital Edition 3.0 documents) suddenly become Adobe Digital Editions 4.5 documents (not all, for some unknown reason, despite the fact that all the pdf documents on my computer were downloaded via Adobe Reader). I definitely do not want this. I could laboriously remove the DRM from each file, but that would be ridiculous. Is the only solution to uninstall 4.5?

Recently I installed the more recent version of Adobe Digital Editions (the new one is 4.5. I had 3.0 -- in fact, I still have also 3.0, as I am not sure whether I can discard 3.0, since 4.5 took over files from 3.0). But then I saw that many of the pdf files on my computer (which were not Adobe Digital Edition 3.0 documents) suddenly become Adobe Digital Editions 4.5 documents (not all, for some unknown reason, despite the fact that all the pdf documents on my computer were downloaded via Adobe Reader). I definitely do not want this. I could laboriously remove the DRM from each file, but that would be ridiculous. Is the only solution to uninstall 4.5?

Most likely what has changed is not the file but the program the operating system or file manager has listed as the default to use in opening that file. Unfortunately, often when one installs a new program, the default setting of the installation program will be to change the OS or file manager defaults so that they use that program as default for opening files of the type it can open.

We see this imperialist behaviour from things like iTunes, QuickTime or Windows Media Player, and their IMage-viewing equivalents, that each make a grab for preference in opening sound or image files.

If this has happened, the icon showing beside the file in your file manager will change, but that doesn't matter. The file itself is untouched.

To fix it you need to change the default program used to open the file type .pdf in your OS or file manager. To find out how to do this, internet-search